Extrusion failure help
Hey gang,
So, I'm pushing 1800 hours of printing on my mk3s+, mostly no issues so far. But the last day or so, I've been absolutely sidelined by the extrusion stepper assembly. Print will start fine, start chugging away, and about an hour in, boom, no more extrusion. The filament gets hung up on.... Something? There's filament all the way through the assembly to the nozzle, but nothing comes out. As a result, the idler wheels grind the hell out of the filament, and it's gets all bound up.
I've tried:
- Loosening idler wheel screw
- Tightening idler wheel screw
- Idler wheel alignment
- New filament
- Old filament
- More cooling
- Leaving enclosure doors open
- Slower/faster speeds
- Prayer
- Threats
Bubkis. Nada. Just constant failures. And on a 40 hour print, that's mildly infuriating.
Any help?
RE: Extrusion failure help
An update:
The idler gear appears to keep coming off the extruder rod, causing total loss of feed. What the hell is causing this? I don't want to reef down on this tiny little set screw, but push comes to shove, Ima weld the little bastard on
RE: Extrusion failure help
A bit of blue thread lock on the set screws. Maybe the threads are stripped already. Is one set screw on the flat side of the shaft?
RE: Extrusion failure help
It was. I tried (perhaps unadvisably so) a small amount of Teflon tape on half of the threads, ran it over night. Seemed to work fine.
Now, I also removed the enclosure. Is it possible it was an overheating issue due to heat creep, causing said grub to back off due to filament blockage?
Check the idler bearings.
Cheerio,
RE: Extrusion failure help
Teflon tape fitting into the threads is a good indication that there is loose play and possibly damage to the threads. Blue thread locking compound would do the same as the Teflon tape if left long enough to cure. Don't use the red since it needs high heat to break the bond. Read the instructions. Blue is used in many devices to stop vibration affects on screws.
Heat can cause thread to loosen as there is a temperature expansion difference between the two materials. I suspect there would be more heat in the gears from the hotend than from being in the enclosure. Another reason to get an IR camera to measure it but it is a great question.